# Earth: A sink or a circuit (a bet with an electrician)

1. Aug 31, 2009

### Good4you

I am a general contractor, and have a bet with my electrician, I wondered what your thoughts are on it.

Here it is:
A generator is sitting on a rubber isolation pad and is in no way Earth Grounded.
A grounding stake is placed in the earth and connected to one side of a light bulb, and the other side of the bulb is connected to the Hot side of the generator.
So the generator’s neutral and ground wires go nowhere.

I think: this is an open circuit and will not work.
The electrician thinks: electricity will flow from the generator, and to ground; which will light up the light bulb.

The electrician thinks the earth is a big electricity sink sucking up all electricity. He thinks that electricity always finds the easiest path to ground. I tried to explain that electricity finds the easiest path to complete a circuit, and the only reason typical household current flows to the earth is because the power plant and power poles are also grounded.

I found this back-up, http://www.allaboutcircuits.com/vol_1/chpt_3/3.html which he thinks is wrong.
What are your thoughts, is one of misinterpreting?
How could I explain this better to him? He asked all his journey the same question, and the whole crew thinks I am crazy.

2. Aug 31, 2009

### Staff: Mentor

You are correct. There is no complete circuit to power the lightbulb.

3. Aug 31, 2009

### The Electrician

Rather than argue about, why don't you just do it? Those guys must have the hardware they could hook up. Just use a little portable Honda generator.

4. Aug 31, 2009

### waht

How about just use a voltmeter from radioshack to measure current. Set it on micro amps, and stick the negative lead to a ground rod, and positive lead to a car battery to make it easier.

5. Aug 31, 2009

### Averagesupernova

I'd say it's time to find a new electrician.

6. Aug 31, 2009

### Phrak

Electricians know electrician-ing. They don't need a know theory of electricity to great extent. It always amazes me how people mangage to get their job done in technical matters, where their connection with theory is so peculiar. They either go by route, or use some methodic device founded by what has worked by route. --then, again, doesn't this descibe all theories? It seems you are putting one of these electrician style theories to the test. I have two brothers and a brother inlaw, all electricians, all with interesting notions.

7. Sep 1, 2009

### stewartcs

LMAO! I was thinking the same thing.

CS

8. Sep 1, 2009

### negitron

Eh, not really. You'll find rather few electricians who have even an EE student's understanding of the beast they work with. They'll generally have some low level understanding of basic circuit theory but beyond that most only have a rough knowledge of electrical theory.

9. Sep 1, 2009

### stewartcs

Eh...we're talking about grounding. Electricians are required to know this (in the US at least) as they apply the NEC during the course of their work. I'm assuming we are talking about a licensed electrician and not an apprentice here.

In fact, my experience with electricians and EE's has shown that the majority of the EE's don't understand grounding/bonding quite as well as electricians do (it's sad actually that they don't teach this as much these days the EE curriculum).

CS

10. Sep 1, 2009

### Pumblechook

At the other end of the scale Profs in some of the World's most prestigious universities can be totally impractical thinking they can prove all sorts of stupid things with mathematics. Engineers with years of experience could tell them in a second they were talking nonsense.

The MIT Prof who thinks he can send power through the air with little loss is an example. I thought it was an April fool when I first saw that one.

11. Sep 1, 2009

### Staff: Mentor

They are required to know what the code requires them to do. They are not required to know why. Of course it would be nice and might be helpful, but if a contractor always did everything by the book, but didn't have an understanding of why, you wouldn't necessarily even know.

One thing about this thought experiment. It is possible to make this work by connecting the neutral side of the generator to a large sphere to act as an electron source. Since in an AC circuit, the electrons just just go back and forth, all you really need to do is give them some room to move. Somewhere there is a youtube of someone doing something like this (yeah, lotta "somes" - I can't find it), but a crystal radio works the same way: the signal oscillates between the antenna and the ground.

12. Sep 1, 2009

### negitron

Just so. That said, if I were having a house rewired and I had to choose between an EE and a master electrician, I'd choose the electrician hands down.

13. Sep 1, 2009

### dlgoff

LOL I'd just do it myself and I'm not an electrician.

I do agree however.

14. Sep 1, 2009

### turbo

I have been upgrading the wiring in this house piecemeal over the years. I have built, modified, and restored many tube amplifiers over the years, and I have a better understanding of the WHY in electrical wiring than most of the electricians that I know.

Most electricians can cook-book through wiring situations and do a really good job, but their troubleshooting skills may be suspect. I called my brother-in-law one night and told him that when heavy loads on one leg or the other of my breaker panel engaged, some lights would dim a little and some would brighten. The power-company service people were unable to tell me why. Reg said "OK, sounds like the neutral at the entrance has lost reference to ground. Open those panels, tighten those clamps and see if that fixes it." Done!

I had told the power company crew members that I thought the secondary transformer had ground-reference problems (our transformer was buried in a vault to provide buried entrance), but I hadn't thought that tightening a clamp in an entrance panel could be the fix. It was.

15. Sep 1, 2009

### Phrak

turbo. When my brother (an electrician) comes down, he insists on doing periodic maintenance. Last time, he loosened the clamps to each of the mains about a sixteenth of a turn then reseated.

16. Sep 1, 2009

### turbo

That was a really good thing to do about 25 years ago (or longer) around here. The clamping standards for Aluminum vs Copper at entrances were a bit flexible for a while. Ask him about that. I'm thinking that he is probably 40 or older and was sensitized by some house-fires in the 80s

17. Sep 1, 2009

### Phrak

I might not see him for a while. He said he was wiping the contacts. And the mains are aluminum. :uhh: Not that it made a difference. He's retired, so without something to fix...

18. Sep 2, 2009

### Averagesupernova

Yes electricians are required to know the code and etc. But the above quote makes me wonder. Wouldn't one of them know better? I've worked with electricians that came up with some stuff that hadn't occurred to me. The same is true in reverse.

Last edited: Sep 2, 2009
19. Sep 2, 2009

### Phrak

Then, I suppose offering to demonstrate you superior knowledge in an experiment where you supply a path to ground is out? I little bit of cash in an even bet would spice things up.

Some Lore I pulled off the internet confuses electicity with current, refers to things like "used electricity", and of course "electricity always seeks ground."

"The hot wire conducts the voltage (electricity under pressure) from the service panel to the appliance or fixture. Because electricity always seeks ground, after it is used it flows back through the neutral wires to the grounding bar in the service panel (but not under pressure)."

Last edited: Sep 2, 2009
20. Sep 4, 2009

### famousken

Yes, but you would need a HUGE sphere in order to provide enough capacitive coupling at 60Hz, I'm talking like a mile diameter. A radio works at much higher frequencies and also requires much less power than a light bulb.

21. Sep 4, 2009

### negitron

That seems rather...large. Can you show the calculations on which you base this assertion?

22. Sep 4, 2009

### Good4you

Well the electrician asked his Manager; who at first started to say that no system is perfect and there will likely be grounding somewhere, somehow so the light bulb will turn on. But when the question was rephrased and he understood i was talking about an isolated generator not a building, he admitted i was right. The electrician reluctantly paid up my \$10 when hearing this from his manager. I'm surprised some of his journeymen are still reluctant to believe me. I wonder if their classes are not teaching the appropriate principles (perhaps teaching only practical applications and no theoretical?)

When really thinking about it, for all intents and purposes it is reasonable for an electrician to assume electricity will always find ground, because all major electrical systems are grounded. When working with generators, though i know theoretically i can touch the hot wire, i'm still not going to risk my life and try it, so i guess it is better to be safe than sorry, and for most electricians it probably doesn't really matter.

23. Sep 4, 2009

### negitron

I have. Usually unintentionally. We build three-phase power equipment which is fed from a 480- or 600-V delta source and is therefore not ground-referenced. I have on occasion accidentally (and once on purpose as a demonstration) made contact with a primary phase. Wearing rubber-soled shoes on a dry, sealed concrete floor I didn't feel a thing.

24. Sep 8, 2009

### stewartcs

They're required to know enough about the "why" to pass the licensing exam. And it covers electrical safety/grounding as does the NEC.

However, I'm quite surprised that a journeyman electrician would not know this. My brother-in-law has been an electrical contractor for over 20 years (his family has been in the electrical business for over 50 years) and was shocked (no pun intended) to hear this story as well (assuming they are licensed of course). If they are not licensed, then he said it would be no big surprise to hear that, since 99% of the jobs they deal with are grounded systems.

Also, as a safety note, DO NOT TOUCH ENERGIZED ELECTRICAL EQUIPMENT!

CS

25. Sep 8, 2009

### negitron

I have to; it's my job.